University of MelbourneVictoria


University of MelbourneVictoria

Time filter
Source Type

Gilson K.-M.,Center for Health Equity | Bryant C.,University of Melbourne | Bryant C.,Royal Womens Hospital | Judd F.,University of MelbourneVictoria
Addictive Behaviors | Year: 2017

Introduction and aims Despite a common perception that older adults drink less than younger adults, drinking frequency increases with age. The aim of this study was to examine the types of coping motives associated with problem drinkers in addition to the types of specific drinking problems most commonly endorsed by older drinkers. The study also sought to investigate the role of individual drinking to cope motives in problem drinking. Method Participants were 288 community dwelling older adults aged who consumed alcohol, and were drawn from a larger study of health and aging in rural areas of Australia. Participants completed a postal questionnaire comprising the Drinking Problems Index, Drinking Motives Questionnaire, The AUDIT-C, and the Centre for Epidemiological Studies Depression Scale. Results Overall, 22.2% of the sample were problem drinkers, with a higher prevalence for men (30.4%) than women (15.6%). Problem drinkers were significantly more likely to consume alcohol according to several indices of risky drinking. The most common drinking problems experienced were becoming intoxicated, spending too much money on drinking, feeling confused after drinking, and skipping meals. Drinking to cope motives to relax, to manage physical symptoms and to feel more self-confident increased the odds of problem drinking. Conclusions Problem drinking is highly prevalent in older adults. Given the potential adverse consequences of problem drinking on the health of older adults it is imperative that health professionals pay attention to drinking behaviours as part of routine practice. © 2016 Elsevier Ltd

MacDougall M.J.,University of Toronto | Tabor N.J.,Southern Methodist University | Woodhead J.,University of MelbourneVictoria | Daoust A.R.,University of Toronto | And 2 more authors.
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2017

The Richards Spur locality, Oklahoma, USA, represents an Early Permian infill in a series of Ordovician limestone and dolostone karst fissures. It exhibits the most diverse terrestrial Palaeozoic community currently known, with > 40 distinct tetrapod taxa. Speleothems intimately associated with the site indicate that Richards Spur is a cave system, suggesting a preservational environment that is distinct from those of more typical Early Permian lowland deltaic/fluvial localities. Fossil material obtained from the caves is often found in disarticulation, although articulated material is not uncommon. This suggests that there were several factors that affected how animal remains became deposited within the caves. Many animals that died outside the caves were likely disarticulated on the surface and then washed in during rainfall events, resulting in mostly disarticulated remains. Alternatively, animals could be washed in before being disarticulated and some probably fell into the caves, resulting in less chance for their remains to become disarticulated. Supporting evidence for these preservational hypotheses comes in the form of wear caused by attritional processes. Disarticulated elements can exhibit high levels of wear, likely due to water transport that would carry them into the caves from the surface, as well as reworking within the caves. The partially and completely articulated remains are normally unworn, presumably due to a lesser degree of transport and reworking. X-ray diffraction and stable isotope analysis of cave infill further supports the interpretations made from fossil material. The results of this study provide a much-improved understanding of the preservational environment at Richards Spur, and will be useful in integrating information from this unique upland locality with that from the more extensively studied lowland localities of the Early Permian. © 2017 Elsevier B.V.

Kashani A.,University of MelbourneVictoria | Ngo T.D.,University of MelbourneVictoria | Mendis P.,University of MelbourneVictoria | Black J.R.,University of MelbourneVictoria | Hajimohammadi A.,University of MelbourneVictoria
Journal of Cleaner Production | Year: 2017

End-of-life waste tyres are known to have negative economic and environmental impacts due to the difficulty associated with their disposal and recycling. The use of recycled tyre crumb (RTC) as a component of construction materials has emerged as a potentially sustainable solution to this environmental issue. There exists extensive research covering the use of RTC as a filler in conventional concrete. However, there are very limited studies focused on insulation properties of RTC in lightweight cellular concrete (LCC) as a sustainable application that can add value to the final product. This study investigates the effects of different RTC contents on compressive strength, porosity, thermal conductivity, sound insulation and water permeability of LCC as an insulator. A rather homogeneous distribution of tyre crumbs within LCC structure was achieved. It has been found that LCC samples containing RTC are suitable as insulators because the sound and thermal insulation are improved as rubber content is increased compared to the sample with similar density but without RTC. The insulation properties of this product also come with the same total porosity and a significant reduction in the rate of water permeability compared to the sample without RTC. 3D restructuring of micro-CT scan images of this composite revealed the effects of tyre crumb on the total and local porosity of this composite. Despite the fact that addition of tyre crumb reduced the strength, surface treatment of crumb rubber with sodium hydroxide solution exhibited significant improvement in the compressive strength of LCC as the result of better physical bonding with hydrated cement proven by scanning electron microscopy (SEM) images and energy dispersive spectroscopy (EDS) analysis. © 2017 Elsevier Ltd

de Jong P.,Federal University of Bahia | Dargaville R.,University of MelbourneVictoria | Silver J.,University of MelbourneVictoria | Utembe S.,University of MelbourneVictoria | And 2 more authors.
Applied Energy | Year: 2017

This study examines the optimal integration of high proportions of wind energy into an electricity grid which traditionally depends on hydroelectricity. Wind power in the Brazilian Northeast (NE) is expected to generate 57% of the NE's electricity supply by 2020. As rainfall in the NE region is susceptible to climate change, it is anticipated that wind energy could substitute lost hydroelectric availability. The Weather Research and Forecasting (WRF) Model is used to simulate wind speeds for all of 2014 and calculate wind power across the entire NE region of Brazil. The NE region's aggregate hourly wind generation and net load curve are then estimated for increasing wind penetrations using the planned rollout of wind farms in the region as a baseline. The maximum wind energy penetration in the region is estimated to be approximately 50% before significant amounts of energy would need to be curtailed or exported to other Brazilian regions. It was found that wind energy generation from coastal wind farms in the region best correlates with the hourly and monthly variations of the NE subsystem's load curve. Conversely, inland wind farms on the NE's elevated plateaus typically generate more power late at night, but have higher capacity factors. © 2017 Elsevier Ltd

Samiee S.,Shahid Chamran University | Kooti N.,Shahid Chamran University | Gable R.W.,University of MelbourneVictoria
Journal of Molecular Structure | Year: 2017

The reaction of new phosphonium-phosphine oxide salt [P(O)Ph2(CH2)2PPh2CH2C(O)C6H4NO2]Br (1) with mercury(II) iodide in a methanolic solution yielded [P(O)Ph2(CH2)2PPh2CH2C(O)C6H4NO2]2[Hg2I5Br](2). These two compounds were fully characterized by elemental analysis, IR, 1H, 31P, and 13C NMR spectra. Crystal and molecular structure of 2 has been determined by means of X-ray diffraction. In mercury compound, the phosphine oxide salt is found as a counter ion letting the mercury(II) ion to bound halides to all four coordination sites and to give dimermercurate(II) ions as the structure-constructing species. The neighboring [P(O)Ph2(CH2)2PPh2CH2C(O)C6H4NO2]2+cations are joined together by intramolecular C[sbnd]H⋯O hydrogen bonds to give a 1-D chain structure along the crystallographic b-axis. The [Hg2I5Br]2−anions act as cross-linkers between neighbouring strands extending the supramolecular structure into 2D layers in (110) planes as well as balances the charge of the complex. The significant effects of C[sbnd]H⋯X (X[dbnd]O, Br and I) and π⋯π aromatic interactions play a major role in the crystal packing of compound 2. © 2016 Elsevier B.V.

Warmerdam A.,Monash University | Newnam S.,Monash University | Sheppard D.,Monash University | Griffin M.,University of Western Australia | Stevenson M.,University of MelbourneVictoria
Accident Analysis and Prevention | Year: 2017

In Australia, more than 30% of the traffic volume can be attributed to work-related vehicles. Although work-related driver safety has been given increasing attention in the scientific literature, it is uncertain how well this knowledge has been translated into practice in industry. It is also unclear how current practice in industry can inform scientific knowledge. The aim of the research was to use a benchmarking tool developed by the National Road Safety Partnership Program to assess industry maturity in relation to risk management practices. A total of 83 managers from a range of small, medium and large organisations were recruited through the Victorian Work Authority. Semi-structured interviews aimed at eliciting information on current organisational practices, as well as policy and procedures around work-related driving were conducted and the data mapped onto the benchmarking tool. Overall, the results demonstrated varying levels of maturity of risk management practices across organisations, highlighting the need to build accountability within organisations, improve communication practices, improve journey management, reduce vehicle-related risk, improve driver competency through an effective workplace road safety management program and review organisational incident and infringement management. The findings of the study have important implications for industry and highlight the need to review current risk management practices. © 2016 Elsevier Ltd

Liong S.,Mercy Hospital for Women | Liong S.,University of MelbourneVictoria | Lappas M.,Mercy Hospital for Women | Lappas M.,University of MelbourneVictoria
Placenta | Year: 2017

Introduction Inflammation and underlying low-grade maternal infection can impair insulin signalling and upregulate nutrient transport in the placenta which contribute to fetal overgrowth associated with GDM and/or obese pregnancies. There are, however, no studies on the role of infection on placental nutrient transport in pregnancies complicated by GDM and/or obesity. Thus, the aims of this study were to determine the effect of the bacterial product lipopolysaccharide (LPS) or the viral dsRNA analogue polyinosinic:polycytidylic acid (poly(I:C)) on the insulin signalling pathway and amino acid transport in primary human trophoblast cells. Methods Human primary villous trophoblast cells were treated with LPS or poly(I:C). Protein expression of insulin signalling pathway proteins, insulin receptor (IR)-β, insulin receptor substrate (IRS)-1 and protein kinase B (also known as Akt), and phosphatidylinositol-4,5-bisphosphate 3-kinase p85α subunit (PI3K-p85α) protein were assessed by Western blotting. Glucose and amino acid uptake were assessed by radiolabelled assay. Western blotting and qRT-PCR were used to determine amino acid transporter protein and mRNA expression, respectively. Results LPS and poly(I:C) significantly decreased phosphorylation of IR-β, IRS-1, Akt, total PI3K-p85α protein expression and glucose uptake. LPS and poly(I:C) also significantly increased expression of System A amino acid transporters SNAT1 and SNAT2, and System A-mediated uptake of amino acids. Discussion LPS and poly(I:C) induces insulin resistance and increases amino acid uptake in human primary trophoblast cells. This suggests that the presence of low-grade maternal infection can contribute to excess placental nutrient availability and promote fetal overgrowth in pregnancies complicated by GDM and/or obesity. © 2017 Elsevier Ltd

Green K.,National Parks and Wildlife Service | Davis N.E.,University of MelbourneVictoria | Robinson W.A.,Charles Sturt University
Australian Mammalogy | Year: 2014

The ability to utilise a diet of shrubs or trees is key to the survival of herbivores in deep snow. However, reduction in snow depth with climate change may allow herbivores into higher elevations where herb fields are dominant. Wallabia bicolor occurs above the winter snowline of the Snowy Mountains in the subalpine zone, whereas Macropus rufogriseus, does not although it is present in alpine Tasmania. The winter diet of W. bicolor in the Snowy Mountains consisted of shrubs, trees, and herbs. With >60% of food sources (shrubs and trees) available above the snow, the change from occupation of habitat below the winter snowline to above requires little change in its diet. Consumption of shrubs, forbs and monocots by M. rufogriseus was similar between the Snowy Mountains and alpine Tasmania. M. rufogriseus includes a high proportion of shrubs in its diet; however, it may be excluded from snow-covered habitat due to a lesser ability to utilise poor-quality browse. Globally, migratory herbivores respond to deep snow with seasonal movements. However, W. bicolor and M. rufogriseus are not migratory and can only occupy higher elevations of the Snowy Mountains as snow depth and duration diminish. Because they do not currently occupy the alpine zone and the vegetation has not evolved to accommodate their presence, their impact on alpine vegetation is likely to be greater than migratory alpine grazers/browsers. © Australian Mammal Society 2014.

Hu Y.,University of MelbourneVictoria | Kelly L.T.,University of MelbourneVictoria | Gillespie G.R.,University of MelbourneVictoria | Jessop T.S.,University of MelbourneVictoria | Jessop T.S.,Deakin UniversityVictoria
Forest Ecology and Management | Year: 2016

Understanding the relationship between community composition and ecosystem function is essential for managing forests with complex disturbance regimes. Studies of animal responses to fire and timber harvesting in forest ecosystems typically focus on a single level of community diversity. Measures of species abundance and diversity at the community level, along with measures of functional diversity that incorporate information on species traits, provide opportunities for complementary insights into biodiversity responses to disturbances. We quantified community and functional responses of a temperate forest lizard community to fire and rotational logging using metrics including species-specific abundance, community abundance, species richness and evenness, as well as trait-based measures of functional diversity. We used non-linear regression models to examine the relationships between reptile data and time since fire and timber harvesting, using sites arrayed along a 30-years post-disturbance chronosequence. We modelled responses separately in two major vegetation types: coastal Banksia woodland and lowland eucalypt forests. Species and community measures offered different insights into the role of fire and logging. Species responses to disturbance differed between disturbance type and vegetation type. Four species exhibited significant population responses to either fire or timber harvesting, while the rest were unaffected by either disturbance. At the community level, species richness and community abundance increased significantly with time since fire in woodland vegetation. In forest vegetation, community abundance decreased with time since fire. Surprisingly, community evenness and functional diversity did not show marked responses to fire or timber harvesting. This is likely a result of trait homogeneity and the asynchrony in species responses to disturbance. We advocate using multiple measures of community composition - incorporating species-specific information, community metrics and functional traits - to ensure a more holistic understanding of disturbance ecology in forest landscapes. © 2016 Elsevier B.V.

Zafari A.,University of MelbourneVictoria | Wei X.S.,University of MelbourneVictoria | Wei X.S.,Tongji UniversityShanghai | Xu W.,University of MelbourneVictoria | And 2 more authors.
Acta Materialia | Year: 2015

Abstract High pressure torsion was conducted to obtain nano-sized β grains in a metastable Ti-5553 alloy. Much finer grains of <50 nm were achieved, compared to >100 nm in a stable Ti-20 wt.% Mo alloy. The more effective grain refinement was attributed to stress induced martensitic transformation in the former, leading to the formation of thin α" plates which divide β grains into smaller domains. Further deformation resulted in a reverse α" to β transformation with decreasing α" sizes, generating a completely nano β grain structure at very large straining. A detailed description of the β grain refinement mechanism is provided. The reverse transformation is shown to be caused by the significantly increased free energy below a critical α" size of ∼10 nm, consistent with experimental observations. It is also calculated that extremely high energies were required for the formation of α" in nano-sized β grains, making further martensitic transformation impossible. It is concluded that the stress induced martensitic transformation and the subsequent reverse transformation are critical to producing nano-grained metastable β Ti alloys. © 2015 Acta Materialia Inc.

Loading University of MelbourneVictoria collaborators
Loading University of MelbourneVictoria collaborators